Field of the invention

The present description relates in general to methods for producing fuel. More specifically, the description relates to methods for producing fuel, such as diesel fuel and gasoline, from carbon-containing material, for example, waste and biomass.

Background

One of the most important raw materials in the current economy is represented by petroleum, a source currently used mainly in the transport sector, in particular for engines of most land, air and rail vehicles.

Petroleum is a limited resource and destined to run out, at least as an economically-exploitable resource, for example, for producing fuels such as diesel fuel and gasoline.

Faced with this situation, identifying alternative carbon sources through which to reduce the need for petroleum is of increasing interest.

Alternative sources to petroleum for fuel production can be represented, for example, by waste. To give an approximate idea of the size of the supply, about 4 billion tons of solid waste is produced annually (half of this being urban waste), and 330 km of sludge from water treatment.

Further alternative sources can be represented, for example, by biomass or rather biodegradable fractions of products, waste and residues of biological origin coming from agriculture (plants and animals), forestry and related industries, including fishing and aquaculture, mowing and pruning from public and private greenery, as well as biodegradable fractions of urban and industrial waste. Biomass contributes to primary energy more than other renewable sources, with an energy contribution of 60 exajoules (EJ).

Liquid fuels derived from biomass include, for example, bioethanol, biodiesel, vegetable oils, and biomethane.

Bioethanol accounts for about 67% of the total biofuel produced to date; it derives from the fermentation of vegetal biomass with a high sugar content (for example, cane, beet, and sweet sorghum) and a high starch content (for example, maize, wheat, barley, rice).

Biodiesel, which represents about 33% of the total biofuel produced to date, is obtained from vegetable oil, such as, for example, rapeseed oil, soybean oil, and corn oil, by a trans -esterification process (generally obtained by means of alcohol in the presence of catalysts).

Vegetable oils can also be used to power electrogenerators.

Biomethane can be obtained from biogas derived from livestock waste and agricultural resources (such as corn and triticale) subjected to carbon dioxide (C0 ₂ ) purification methods.

Producing first-generation biofuels from plant biomass may have the disadvantage of subtracting resources very often derived from countries such as South America, India, Southeast Asia and Africa, countries that base their economy on the primary sector and whose plant resources could be destined for the feeding and survival of less well-off social classes.

Identifying biomasses that do not derive from dedicated crops, i.e. of non food origin is therefore of fundamental importance and has also been implemented by European bodies with the priority to develop so-called “advanced” fuels, or rather, fuels derived from sustainable biomass such as by products of biological origin coming from agriculture, livestock, agro-industry and biodegradable fractions of products and waste, as well as special and industrial urban waste.

Methods known - to date - for producing synthetic fuels, such as diesel fuel and gasoline, can mainly be traced back to two main methods that make it possible to produce these fuels from coal: direct liquefaction (DL) or rather, the transformation of carbon into liquid hydrocarbons in a single step by means of a hydrocracking process and indirect liquefaction (IL), or rather, carbon gasification into synthesis gas and the subsequent Fischer-Tropsch catalytic process.

The first attempts concerning direct coal liquefaction (DCL) were carried out in Germany starting from 1920, by Friedrich Bergius. The method involved direct hydrogenation of the coal at high temperatures (430-480°C) and high pressure (above 300 bar). To facilitate hydrogenation and avoid erosion problems of the materials, coal was fed into the reactor in the form of a suspension in oil. The reaction was catalyzed by ferrous-based materials such as iron oxide.

Another direct liquefaction method consists of pyrolysis (thermo-chemical process in the“absence” of air). However, problems found in the oils produced by this method limit its use for generating thermal energy in boilers. Furthermore, preparing the raw materials, if waste and biomass are used, including the steps of drying, grinding, inert separation, deferrization and sifting, can be costly in terms of energy. Moreover, the oil produced by this method may have high viscosity values (ranging from 25 to 1000 cSt according to the input material) tending to increase at temperatures of 40-50°C, containing carbon residues acting as catalysts, for forming heavy hydrocarbons, a high concentration of water (50- 70%), a high percentage of oxygen (45-50% of the mass), high acidity (pH 2-3.5 for lignocellulose materials), and low calorific value (13-18 MJ/Kg).

Additional solutions have been proposed and developed more recently to improve the performance and affordability of direct coal liquefaction technology, in particular in hydrogenation techniques, in an attempt to make this technology a truly viable option for producing synthetic fuels as alternatives to those obtained from oil.

However, although the direct liquefaction of fossil coal, from an energy efficiency point of view (the ratio between the chemical energy of the products of the process and that of the input fuel), represents one of the best technologies for producing synthetic fuels, there are still also critical issues - to date - due to high plant costs, due to the consumption of hydrogen and catalysts, and high energy expenditure.

The methods of indirect liquefaction (IL) have increased in development following the method of Friedrich Bergius. Indirect liquefaction methods were devised by Franz Fischer and Hans Tropsch, and the technology for indirectly converting coal into hydrocarbon mixtures is today known as Fischer-Tropsch (FT) synthesis.

The method, briefly, includes the steps of i) gasification of coal to produce synthesis gas with a H ₂ /CO ratio between 1 and 3, ii) cooling and purification of the synthesis gas from tar, sulfur, nitrogen, phenols and other secondary substances, iii) feeding of the synthesis gas into catalytic processes in which hydrogen (H) and carbon monoxide (CO) react to produce liquid hydrocarbons from which liquid fuels are obtained by refining.

The yield of the indirect liquefaction method is relatively low, generally with a ratio between raw material input and synthetic fuel production equal to 5- 7:1. The indirect liquefaction method was created to produce synthetic fuels from coal and natural gas. More recent applications of the indirect liquefaction method have also been developed using biomass and waste as raw materials; these applications, however, have not had an important follow-up from a commercial point of view due to a sub-optimal yield in terms of fuel production; the complexity involved in treating the starting material; the need to calibrate the H ₂ /CO ratio in the synthesis gas, and due to the need to clean the synthesis gas obtained.

In light of the above, there is a growing interest in developing liquefaction methods for carbon-containing materials derived from biomass and/or waste, for producing synthetic fuels that are simple, effective and economical.

Summary of the invention

The present description aims to provide liquefaction methods of carbon- containing material preferably selected from biomass, waste and relative combinations, for producing synthetic fuel, such as gasoline and diesel fuel, which do not involve changes to the current methods of transport, storage and consumption.

According to the present description, the above object is achieved thanks to the subject to which specific reference is made in the following claims, intended as an integral part of the present description.

One embodiment of the present description provides a method for producing synthetic fuel comprising the steps of:

i) providing a carbon-containing material selected from biomass, waste, and combinations thereof,

ii) subjecting said carbon-containing material to carbonization, carried out by at least one treatment selected from the group consisting of pyrolysis, gasification, combustion, roasting, and hydrocarbonization,

to obtain a mixture comprising coal,

iii) submitting said mixture comprising carbon to at least one of:

- Electro-Pulse Hydrogenated Cracking carried out in at least one reactor comprising at least one electric pulse generator, and

- non-Local Thermodynamic Equilibrium (nLTE) plasma treatment carried out in at least one reactor comprising at least one nLTE plasma generator,

for obtaining a mixture comprising synthetic fuel.

In one or more embodiments, water is added to said carbon-containing material provided in step i).

In one or more embodiments, said carbonization step ii) is carried out by hydrocarbonization, wherein said carbon-containing material is subjected to heating at a temperature of greater than l80°C, preferably between l80°C and 370°C, more preferably between 200°C and 220°C, and at a pressure between 1

MPa and 21 MPa, preferably between 1.5 and 2.3 MPa.

In one or more embodiments, the mixture comprising coal obtained from said hydrocarbonization step further comprises water to form a water-coal mixture.

In one or more embodiments, the carbon-containing material subjected to the hydrocarbonization step may comprise an aqueous component ranging from 40 to 80% by weight, preferably equal to 75% by weight with respect to the total weight of the material.

Preferably, the hydrocarbonization step has a duration of greater than 1 hour, preferably between 1 hour and 6 hours, more preferably between 1 hour and 1.5 hours.

In one or more embodiments, water can be added to said mixture comprising coal obtained from said step ii). In one or more embodiments, at least one oil can be added to said mixture comprising coal obtained from said step ii). In one or more embodiments, at least one liquid hydrocarbon can be added to said mixture comprising coal obtained from said step ii). In one or more embodiments, at least one oil and at least one liquid hydrocarbon are added to said mixture comprising coal obtained from said step ii).

In one or more embodiments, water and/or at least one oil and/or at least one liquid hydrocarbon can be added to the mixture comprising coal obtained from the carbonization step ii), which is subsequently subjected to Electro-Pulse Hydrogenated Cracking (EHC) and/or non-Local Thermodynamic Equilibrium nLTE plasma treatment. For example, the mixture comprising coal obtained from the carbonization step ii) to be subjected to Electro-Pulse Hydrogenated Cracking (EHC) and/or non-Local Thermodynamic Equilibrium nLTE plasma treatment may comprise coal in a quantity between 35 and 70% by weight with respect to the total weight of the mixture, water in a quantity between 5 and 60% by weight with respect to the total weight of the mixture, at least one oil and/or at least one liquid hydrocarbon in a quantity between 0 and 40% by weight with respect to the total weight of the mixture.

In one or more embodiments, the mixture comprising coal, optionally supplemented with at least one oil and/or at least one liquid hydrocarbon, to be subjected to Electro-Pulse Hydrogenated Cracking (EHC) and/or non-Local Thermodynamic Equilibrium nLTE plasma treatment may further comprise at least one catalyst, preferably ground or liquid, for example, Iron (Fe)- or Iron- Cobalt (Fe-Co)-based.

In one or more embodiments, the at least one electric pulse generator for Electro-Pulse Hydrogenated Cracking comprises at least one pair of electrodes. Said pair of electrodes is configured for discharging electrical pulses in the mixture comprising coal. For example, in various embodiments, the electric pulses generated by Electro-Pulse Hydrogenated Cracking are generated by an electric circuit by means of a voltage greater than 1 kV, preferably between 1 and 500 kV, more preferably between 5 and 80 kV.

In various embodiments, electric pulses generated in the reactor for Electro-Pulse Hydrogenated Cracking have a repetition frequency greater than 0.1 Hz, preferably between 0.1 and 1000 Hz, more preferably between 10 and 80 Hz. In one or more embodiments, said electric pulses generated in the reactor for Electro-Pulse Hydrogenated Cracking last between 10 ns and 400 ps, preferably between 10 ns and 20 ps.

In one or more embodiments, the nLTE plasma generator is configured to generate plasma by means of an electric pulse generator. In one or more embodiments, the plasma generator may comprise electrodes. In one or more embodiments, the electric pulses for generating the nLTE plasma are produced by an electric circuit by means of a voltage greater than 1 kV, preferably between 1 and 150 kV, more preferably between 1 and 10 kV. In various embodiments, the nLTE plasma generator generates electric pulses with a frequency greater than 1 KHz, preferably between 5 and 100 KHz, more preferably between 5 and 20 KHz. In one or more embodiments, the plasma generator nLTE generates electric pulses lasting between 5 ns and 300ps, preferably between 20 ns and 10 ps.

In one or more embodiments, the nLTE plasma generator is configured to generate plasma on the surface of and through a liquid. For example, plasma can be generated on the surface and through a continuous flow of liquid.

In one or more embodiments, step iii) comprises:

- subjecting the mixture comprising coal to Electro-Pulse Hydrogenated Cracking carried out in at least one reactor comprising at least one electric pulse generator, for obtaining a mixture comprising synthetic fuel and

- subjecting said mixture comprising synthetic fuel to non-Local

Thermodynamic Equilibrium (nLTE) plasma treatment carried out in at least one reactor comprising at least one nLTE plasma generator.

In one or more embodiments, the mixture comprising synthetic fuel obtained by Electro-Pulse Hydrogenated Cracking (EHC) treatment and/or non- Local Thermodynamic Equilibrium plasma treatment can be subjected to a separation and/or refining step of the synthetic fuel.

In one or more embodiments, the method may comprise an upgrade step of the synthetic fuels obtained by the refining step.

Brief description of the drawings

The invention will now be described, by way of example, with reference to the attached figures, wherein:

- Figure 1 shows a schematic representation of a method for producing synthetic fuels according to an embodiment of the present description;

- Figure 2 shows a schematic representation of a step of the method according to an embodiment of the present description;

- Figures 3A and 3B show a schematic representation of a step of the method according to embodiments of the present description.

Detailed description of preferred embodiments

In the following description, several specific details are provided to allow a thorough understanding of embodiments. The embodiments may be implemented in practice without one or more of the specific details, or with other methods, components, materials, etc. In other cases, well-known structures, materials or operations are not shown or described in detail to avoid obscuring certain aspects of the embodiments.

Reference throughout the present description to“one embodiment” or“an embodiment” indicates that a particular aspect, structure or characteristic described with reference to the embodiment is included in at least one embodiment. Thus, forms of the expressions“in one embodiment” or“in an embodiment” at various points throughout the present description do not necessarily all refer to the same embodiment. Moreover, the particular aspects, structures or characteristics can be combined in any convenient way in one or more embodiments. The titles provided in this description are for convenience only and do not interpret the scope or object of the embodiments.

In one or more embodiments, the term“synthetic fuels” means fuels derived from coal, natural gas, biomass and waste, preferably through the chemical and/or physical conversion into synthetic raw materials and/or liquid synthetic products.

For the purposes of the present description, the terms “bioliquid”,

“biofuel”, “advanced fuel”, “advanced biofuel”, “innovative fuel”, “synthetic petroleum (or oil)” and“synthetic fuel” are considered synonymous, regardless of the meanings attributed to these terms by current national and international regulations concerning bioliquids, biofuels, advanced biofuels, and synthetic fuels.

The method subject of the present description allows production of synthetic fuel, such as, for example, diesel fuel and/or gasoline, starting from a material comprising carbon selected from biomass, waste and relative combinations.

For the purposes of this description, the term “biomass” means the biodegradable fraction of products, waste and residues of biological origin from agriculture (plants and animals), forestry and related industries, including fisheries, aquaculture, and the mowing and pruning from public and private greenery. The term biomass also refers to the biodegradable portion of urban and industrial waste.

In one or more embodiments, the biomass used in the method subject of the present description may comprise, for example, by-products derived from agro-zootechnical and/or agro-industrial applications. Below are some examples of biological by-products that can be used in the method described. With reference to by-products from applications in the agricultural sectors, by-products derived from crops such as, for example, cereal crops, maize, triticale, oil seed, tree plantations, for example, fruit trees (for example, grapevines, olive trees, etc.) can be considered. With reference to zootechnical applications, by-products such as manure, pollen and farm debris can be considered. In addition, by-products derived from horticulture, aquaculture, forestry and tree plantations and from public and private green areas (from cleaning and maintenance) are included.

With reference to agro-zootechnical-industrial applications, by-products from the processing of cereals, fruits and vegetables can be included (for example, processing of grapes, olives, oil seed in general, tomatoes, citrus fruits, beets, sugar cane), slaughterhouse waste and from the woodworking industry can be considered. Biomass also refers to the biodegradable parts of urban waste and similar waste such as, for example, from catering, community, markets, industrial waste and anything else associated with the definition of biomass.

The term“carbonization step” refers to a coal generation/production step. In one or more embodiments, waste can comprise urban waste and special waste, including industrial waste.

Urban and/or special waste, including industrial waste, can be selected, for example, from: urban waste possibly subjected to mechanical separation, also deriving from recycling collection; special industrial waste, for example, from food preparation and processing, such as sludge and waste unusable for consumption or processing; waste from woodworking activities and production of furniture and panels; waste from processing of paper and cardboard, for example, sludge and pulp; waste from the textile and fur industry, for example, processing waste, meat scraps, fats, leather parts; waste from oil refining, for example, oils, oil sludge, from waste oils and fuel residues; waste from packaging, sanitary towels, waste treatment and civil and industrial water treatment, for example, sludge and non-recyclable parts; waste from energy production plants such as, for example, carbon from pyrolysis and gasification; digestate from biogas; and waste from aerobic and anaerobic treatments, such as non-standard compost. Most of these materials can be classified as by-products if they prove to be effective.

In one or more embodiments, the material comprising carbon, which can be used in the method subject of the present description, may contain an aqueous component from 40 to 80% by weight.

In one or more embodiments, the material comprising carbon, which can be used in the method subject of the present description, may comprise solid fragments, preferably smaller than 20 cm.

The method subject of the present description is hereinafter described with reference to Figures 1 to 3.

Figure 1 shows a diagram of an embodiment of the synthetic fuel production method according to the present description.

Biomass and waste comprising solid materials that can be shoveled, and pumpable liquid materials can be stored in special containers, for example, shown in Figure 1 with reference numbers 10 and 11.

In one or more embodiments, the aforesaid materials are loaded into a hopper of a preparation plant 20 by using, for example, mechanical blades or systems known in the art for transferring solids and liquids (e.g. with reference to the transfer of liquid pumping systems).

In one or more embodiments, water can be added to the carbon-containing material.

In the hopper of the preparation plant 20, water preferably derived from recirculation 110 and/or from an external source, for example, from an aqueduct or a well 12, can be added, in a quantity whereby the material subjected to the subsequent steps of the method will contain a water component, for example, between 70-80%.

Water is not added if the starting material comprises an aqueous component in a sufficient quantity as, for example, may happen when using digestate from biogas production and sludge from purification of civil and industrial water.

In one or more embodiments, water may be added in a quantity from two to four times the dry weight of the carbon-containing material.

For example, when using a quantity of material (for example, organic material from urban waste), for a mass of 22 kg with a quantity of water of 54% and a dry mass of 10 kg, a quantity of water equal to 18 kg may be added to achieve a total mass of 40 kg with 75% water.

In one or more embodiments, the method may comprise a preparation step of the material comprising carbon possibly supplemented with water. For example, the preparation step can envisage subjecting the material comprising carbon to at least one treatment chosen from separation, grinding and homogenization.

In various embodiments, the aforesaid preparation steps of the material can be carried out in a single machine. In one or more embodiments, for grinding the carbon-containing material having a size of more than 20 cm, a double-shaft or poly-shaft blade grinder can be used, or a“bag -breaker” in the presence of material in bags.

In one or more embodiments, inert and metal components can be separated from the material possibly supplemented with water, as described above, which are automatically discharged at a predetermined time sequence or manually extracted and stored in a suitable container 21.

Although they are neutral components for the method, these components, such as glass, stones and metals, could alter the characteristics and the yield of the final product, as well as any traces of iron oxides (Fe), which could exert an undesired catalytic activity. In one or more embodiments, the separation can be carried out in a chamber in which the material is subjected to a vortex motion capable of expelling the aforesaid inert components.

After the step of separating the inert components and metals, the material can be further subjected to grinding and homogenizing by means of blades and by using a grid with a mesh size between 10 and 40 mm, preferably 20 mm.

The flow rate of the input material and water can vary, for example, from 50 to 100 liters in batches at 2-3 m /h to 10 m /h, up to values of greater than 100 m /h with powers installed for the treatment from 2.2 kWe to 12 kWe. Pumping can be performed, for example, with an eccentric screw pump or similar functional systems.

In one or more embodiments, the material possibly supplemented with water and possibly mixed and ground has a homogeneous consistency (homogeneous slurry). Otherwise, the material can be transferred several times from the preparation plant 20 to a tank for intermediate storage or pre carbonization tank 30.

In one or more embodiments, the carbon-containing material is subjected to a carbonization (or coal-generating) step, said step being carried out by means of at least one treatment selected from the group consisting of: pyrolysis, gasification, combustion, roasting, and hydrocarbonization, to obtain a mixture comprising coal.

Preferably, the carbon-containing material, possibly subjected to a step in which water is added, is subjected to hydrocarbonization.

In various embodiments, the carbonization step is carried out by hydrocarbonization; in said hydrocarbonization step, the carbon-containing material, possibly supplemented with water, is subjected to heating at a temperature of greater than l80°C, preferably between l80°C and 370°C, more preferably between 200°C and 220°C, and at a pressure from 1 MPa to 21 MPa, preferably between 1.5 and 2.3 MPa, as described below.

In one or more embodiments, the method may comprise a pre-heating step that precedes the hydrocarbonization step. This step can be carried out in the pre carbonization tank 30.

In one or more embodiments, the pre-heating step of the material is carried out at a temperature from 70°C to 95°C, preferably between 80°C and 90°C.

In one or more embodiments, for heating the material it is possible to use, for example, the heat recovered from the method, for example, by passing the fumes from the electrogenerator 170 (if installed) in a suitable jacket or in pipes external to both the pre-carbonization tank and to the reactor of the hydrocarbonization step 40. In addition, supplementary/alternative systems such as, for example, an HHO burner (gas produced by water) can be used, with appropriate systems to avoid direct contact of the flame with the reactor, microwaves, electric plates, burners of oil/fuel produced by the method, natural gas/ LPG burner.

In one or more embodiments, the carbonization step by means of hydrocarbonization can be carried out in batches. In this case, the material is conveyed by a suitable pump from the pre-carbonization tank 30 to the hydrocarbonization reactor 40. The pre-carbonization tank 30 may have a capacity equal, for example, to 1.5 times the volume of the hydrocarbonization reactor 40.

In one or more embodiments, the hydrocarbonization step may be carried out at an acidic pH, from 4.5 to 6.5, preferably equal to 6. The acid working environment has the advantage of speeding up the process and improving the quality of the final product.

In one or more embodiments, the hydrocarbonization step can be carried out in the presence of at least one catalyst selected, for example, from acetic acid, citric acid, sulfuric acid and relative combinations.

In one or more embodiments, the catalyst can be fed directly into the pre carbonization tank 30, for example, from a suitable storage tank 31 by means of a suitable pump or other suitable system for solids, for example, by means of a piston or star valve system. In the case of using an acid catalyst, the acidity can be calibrated, for example, by evaluating variations in pH with respect to the pH of the recirculated water 110.

Feeding of the catalyst into the pre-carbonization tank 30 may prove to be advantageous, especially in the case of recirculation of the material comprising carbon in the preparation plant 20, so as to obtain a homogeneous and optimal material for the subsequent process.

In one or more embodiments, feeding of the catalyst can also be carried out by means of a special mixing pipe with a vortex motion 32 inserted into the passage between the pre-carbonization tank 30 and the hydrocarbonization reactor 40 or directly into the latter, or even into the hopper of the preparation plant 20.

In one or more embodiments, the hydrocarbonization step can be carried out continuously as well as in batches (discontinuous manner).

In one or more embodiments, the hydrocarbonization step can be carried out, for example, in tubular reactors, in in-out pipes in which part of the process occurs, and in a reactor/tank, or in a tank with stirring.

In one or more embodiments, the hydrocarbonization step performed in batches can have the advantage of obtaining a reduction in the cost of the method since discontinuous systems are generally less expensive and simpler in terms of construction compared to continuous systems.

In one or more embodiments, the hydrocarbonization step can be carried out in a hydrocarbonization reactor 40 such as, for example, a vertical tank, made of stainless steel, equipped with internal mixing by, for example, blades fitted onto a vertical axis.

In one or more embodiments, the hydrocarbonization reactor 40 can be made in such a way as to support pressures of at least twice the maximum operating pressure (generally a pressure of between 3 MPa and 5 MPa, but also higher). The reactor 40 can also have control and emergency valves, pressure switches and thermostats. In one or more embodiments, the reactor 40 can have one-way vent valves which allow the pressure to be controlled and excess pressure to be prevented.

In one or more embodiments, the hydrocarbonization reactor 40 can be filled with the material comprising carbon, optionally supplemented with water, coming from the pre-carbonization tank 30, preferably up to 60-90% of its volume. It is preferable that about 15% of the reactor capacity is left free.

In one or more embodiments, the hydrocarbonization step can be carried out in the absence of air. In one or more embodiments, the carbon-containing material, optionally supplemented with water, subjected to the hydrocarbonization step comprises an aqueous component ranging from 40 to 80% by weight, preferably equal to 75% by weight.

In one or more embodiments, the material contained in the hydrocarbonization reactor 40 has no exposed solid parts in order to avoid the pyrolysis effect or rather, pirogas generation with loss of carbon.

In one or more embodiments, the water added to the material comprising carbon that can be used in the hydrocarbonization step can, for example, be water recirculated from the method. The recirculated water can cause an increase in the yield of coal obtained with respect to the use of water, for example, from an aqueduct or a well.

In one or more embodiments, the material comprising carbon contained in the hydrocarbonization reactor 40, suitably closed by appropriate valves at the level of the in-out ducts, is subjected to heating.

In one or more embodiments, the temperature of the hydrocarbonization step is greater than l80°C, preferably from l80°C to 370°C, more preferably between 200°C and 220°C.

In one or more embodiments, the pressure to which the material is subjected in the hydrocarbonization step 40 is from 1 MPa to 21 MPa, preferably between 1.5 and 2.3 MPa.

In one or more embodiments, the hydrocarbonization step lasts more than 1 hour, preferably from 1 to 6 hours, more preferably between 1 hour and 1.5 hours.

During the hydrocarbonization step, the provision of heat for heating the material is constantly controlled in order to avoid excessive heating, since the process underlying the hydrocarbonization step is an exothermic process.

The material subjected to the hydrocarbonization step undergoes reactions of hydrolysis, dehydration and decarboxylation in which, among other things, the molar ratios of hydrogen/carbon (H/C) and oxygen/carbon (O/C) are reduced, shifting the material in the carbonization diagram, in general, into the areas of brown coal (lignite).

Following the hydrocarbonization step, a solid is produced similar to brown coal or lignite due to its elemental composition and its calorific value. The granulometry of the product has a dimension from 20 to 200 micrometers (pm), preferably equal to 80 pm.

The calorific power of the product, coal, obtained from the hydrocarbonization step of materials comprising carbon such as, for example, biomass and waste, has values comparable to the calorific value of brown coal and lignite. To give some examples, for the organic part of urban waste, the lower calorific value (lev) of the coal produced is between 6 and 7.5 kWh/kg (21.6 - 27 MJ/kg), while the average value for this product not subjected to hydrocarbonization is 2.3 kWh/kg (8.28 MJ/kg). For depuration sludge, the lev of the coal produced is, on average, between 3.5 and 5 kWh/kg (12.6 - 18 MJ/kg), while the average value for the same material not subjected to hydrocarbonization is 0.9 kWh/kg (3.24 MJ/kg). For vegetative material derived from pruning, the lev of the coal obtained is, on average, between 4.5 and 6 kWh/kg (16.2 - 21.6 MJ/kg) against an average initial value of 3.3 kWh/kg (11.88 MJ/kg).

With reference to the yield from the hydrocarbonization step, the production of coal may vary according to the operating parameters used and the materials of origin; for example, by exposing the material comprising carbon supplemented with water to a temperature ranging from 200 to 235°C, a pressure of 1.5 to 3 MPa, and a residence time in the reactor 40 of 1.5 to 2 hours, it is possible to obtain a quantity of coal between 62% and 80% by weight of the input anhydrous material, for example of organic matter from urban waste and vegetative material derived from pruning.

In the residual water of the hydrocarbonization step it is possible to detect traces of carbon known as total organic carbon (TOC), such as organic acids, sugars and derivatives of both sugars and lignin. The quantity of these traces can be reduced with increasing temperature and reaction times.

In one or more embodiments, the residual water of the hydrocarbonization step can be used for irrigating crops (for example, in greenhouses or for hydrocultures), or can be purified with known technologies and discharged into surface waters. This use is generally made possible when the starting materials have a high water component (such as for depuration sludge, digestate from biogas, citrus fruit pulp), and therefore the addition of water from recirculation is not necessary 110.

With reference to the energy consumption of the hydrocarbonization step, in general, and by way of example, performing this step at a temperature of 220°C, with a residence time in the reactor 40 of 1.5 hours, without any energy recovery entails a thermal consumption parameterized on the material equal to 120-400 Wh per kg of starting material, and electrical consumption of between 10 and 60 Watt per kg of material. The thermal consumption decreases substantially with the activity of energy recovery or alternatively/in integration with the preferential use of a low energy consumption HHO burner which heats up the plates that act as heat transfer elements for the reactor (for example, the electrical consumption may be estimated between 6 and 30 Watts h per kg of materials to be heated from l0°C to 2lO°C).

In one or more embodiments, the method may comprise a step of cooling the water-coal mixture obtained with the hydrocarbonization step.

Once the hydrocarbonization step has ended (before opening the in-out valves of the reactor 40), the coal-containing mixture obtained is cooled by lowering the temperature to below l00°C, preferably between 60 and 70°C. In one or more embodiments, the cooling can be carried out, for example, by passing cold water onto the walls of the reactor in suitable pipes or with forced air ventilation.

In one or more embodiments, cooling can take place by means of a cooling circuit 180, preferably using water. This circuit can be composed of free cooling modules 181, with a possible closed-circuit adiabatic sub-cooling.

In one or more embodiments, after the cooling step, the mixture comprising coal (slurry) is conveyed, by means of a suitable pumping system, into a holding tank 50 which can have a volume equal to 1.5-2 times the volume of the hydrocarbonization reactor 40. This mixture comprising coal also contains water.

In one or more embodiments, the holding tank 50 can be connected to the cooling circuit 180 to maintain a temperature in the tank that is preferably between 30 and 50°C or lower.

In one or more embodiments, the method provides a step of calibrating the amount of water and coal contained in the mixture following the hydrocarbonization step. The calibration step envisages preparing an optimal mixture comprising coal and water for the subsequent steps.

The holding tank 50 can also assume the function of calibrating the quantities of water and carbon present in the material subjected to hydrocarbonization.

For example, since coal is generally hydrophobic, it is possible to obtain its concentration by decantation. The excess water can be sent to the recirculation tank 110, after appropriate separation from the coal residues, for recirculation in the tank 50, for example, by means of a self-cleaning filter 51.

In one or more embodiments, it is also possible to use a filter press to calibrate the quantities of water and coal present in the material subjected to hydrocarbonization, after measuring the humidity of the solid component; in this case as well the excess water is sent to storage 110.

Moreover, in one or more embodiments, to increase the accuracy of calibration of the quantities of water and coal present in the material subjected to hydrocarbonization, a hydrocyclone can be used, which can perform the function of solid-liquid separation.

The advantage of the calibration step is that of optimizing the subsequent processes that intervene on the carbon and water molecules and the quantities, which affect the final results (for example, the production of synthetic oil).

The coal-water mixture obtained from the hydrocarbonization step, after calibration, can be kept in constant movement in the holding tank 50 so as to avoid separation of the materials, for example, by means of blades on a vertical axis.

In one or more embodiments, once the hydrocarbonization reactor 40 is emptied, the cycle restarts with a new supply of the reactor 40 with material contained in the pre-carbonization tank 30. At the same time, the holding tank 50 is emptied and the material contained therein is conveyed into a mixing tank 60 for a subsequent step of the process, in a continuous cycle.

In one or more embodiments, it is also possible to provide a coal mass that has already been produced. In this case, the method would comprise the steps of i) supplying a coal-containing material and ii) subjecting said coal-containing material to Electro-Pulse Hydrogenated Cracking conducted in at least one reactor comprising at least one electric pulse generator, and/or non-Local Thermodynamic Equilibrium (nLTE) plasma treatment conducted in at least one reactor comprising at least one nLTE plasma generator as described below.

The method may also envisage providing a coal mass already produced and stored in a suitable container 13 (Figure 1) also with other known state-of-the- art methods, for example, with thermal, electric, and micro-wave processes. Furthermore, for example, fossil coal, lignite, brown coal, or charcoal could be used. In this case, the material would not be subjected to the preparation step 20 or coal generation, preferably hydrocarbonization 40. The material could subjected only to grinding, for example, by vortex 202, until particles with sizes between 80 and 120 pm are obtained. The material, optionally ground, would be stored and then conveyed, with a suitable dosing system (for example, with a star valve) into the mixing tank 60 or, alternatively, into the holding tank 50.

In one or more embodiments, the method may comprise the step of adding at least one oil to the mixture comprising coal.

In one or more embodiments, the method may comprise the step of adding at least one liquid hydrocarbon to the mixture comprising coal.

In one or more embodiments, the at least one oil and/or at least one liquid hydrocarbon can be selected from heavy oil produced by refining synthetic oil 140, other products derived from refining, such as, for example, kerosene 161, gasoline 160, diesel fuel 150, and also liquid hydrocarbons and/or oils 142.

Furthermore, liquid hydrocarbons can also be selected from, for example, fuels, solvents, non-standard fuels, oils, for example, industrial oils or lubricants with a natural, mineral or synthetic base.

In one or more embodiments, the mixing tank 60 can be fed with oils 140, oils and/or liquid hydrocarbons 142, optionally catalysts 141, optionally kerosene 161 and/or gasoline 160 and/or diesel fuel 150, water, for example, from recirculation, but also optionally from an external source 12 with appropriate dosing systems (for example, with metering pumps). In various embodiments, the water preferably from recirculation is generally used in the case in which carbon that is not derived from hydrocarbonization is used as a raw material. In one or more embodiments, oils and/or liquid hydrocarbons and any catalysts can also be inserted directly into the holding tank 50.

In one or more embodiments, the mixture comprising coal to be subjected to Electro-Pulse Hydrogenated Cracking and/or plasma nLTE may have the following composition: i) carbon in a quantity from 35 to 70% of the total weight of the mixture, ii) water in a quantity from 5 to 60% of the total weight of the mixture, iii) at least one oil and/or at least one liquid hydrocarbon in a quantity from 0 to 40% of the total weight of the mixture.

The relative quantities of components i), ii), iii) may vary; for example, the material may comprise 50% coal, 25% water and 25% of at least one oil and/or at least one liquid hydrocarbon; or 40% coal, 50% water and 10% of at least one oil and/or at least one liquid hydrocarbon.

In one or more embodiments, the mixing tank 60 can also act as a “destroyer” and“homogenizer”, for reducing the size of the solids contained in the material to be treated (if necessary). For this purpose, a sonic cavitation method can be used, for example, (using an ultrasound intensity, for example, greater than 15-20 W/cm and a frequency of 20 KHz).

In one or more embodiments, the mixture comprising carbon optionally supplemented with water and/or at least one oil and/or at least one liquid hydrocarbon can be subjected to a homogenization step, for example, by means of vortex motion or cavitation activated by transducers immersed in the chamber 60.

In one or more embodiments, the mixture comprising carbon, optionally supplemented with water and/or at least one oil and/or at least one liquid hydrocarbon, can further comprise at least one ground or liquid catalyst, for example, which is iron (Fe)- or Iron-Cobalt (Fe-Co)-based 141.

In one or more embodiments, the at least one oil and/or at least one liquid hydrocarbon possibly contained in the mixture comprising carbon can optionally be pre-mixed with at least one ground or liquid catalyst, for example, that is iron (Fe)- or Iron-Cobalt (Fe-Co)-based 141.

In one or more embodiments, the method comprises a step wherein the mixture comprising coal, optionally supplemented with water, or at least one oil and/or at least one liquid hydrocarbon is subjected to at least one treatment selected from:

- Electro-Pulse Hydrogenated Cracking carried out in at least one reactor comprising at least one electric pulse generator, and

- non-Local Thermodynamic Equilibrium (nLTE) plasma treatment carried out in at least one reactor comprising at least one nLTE plasma generator.

In various embodiments, the Electro-Pulse Hydrogenated Cracking (EHC) step can be carried out in a reactor 70 comprising at least one electric pulse generator, preferably comprising at least one pair of electrodes.

In one or more embodiments, in the reactor, pulsed electric discharges (sparks) are generated - by means of electrodes - in the mixture comprising coal possibly supplemented with water, at least one oil and/or at least one liquid hydrocarbon.

These electrodes can be connected to an electrical circuit to generate electric pulses (pulse generator). In summary, the electric pulse is generated in the electrical circuit, which generates the spark of short duration and high voltage in the liquid by means of the electrodes; the spark generates sonic pressure waves to which the described phenomena are connected (cavitation, etc.).

The Electro-Pulse Hydrogenated Cracking (EHC) reactor 70 schematically comprises a metal container and a pulse generator such as, for example, an electrical circuit, connected to electrodes.

In one or more embodiments, the electrical circuit generates electric pulses to produce intermittent sparks in a liquid environment.

The EHC effect is obtained through a relatively slow accumulation of energy and the relative almost instantaneous release into a liquid. This physical principle is used, albeit rarely, to grind materials such as stones and mining materials and to deform metal objects (such as sheet metal).

The EHC reactor 70 has a suitable conformation so that all the mixture (or slurry) deriving from the mixing tank 60 can be subjected several times to the process, in particular to the effect of the sparks.

In one or more embodiments, the EHC reactor 70 may comprise a pipe (for example, connected to the mixing tank 60 and/or the holding tank 50) in which the mixture comprising coal (or slurry) flows, suitably pumped or by means of gravity.

In one or more embodiments, pairs of electrodes connected to spark generating units can be arranged at regular intervals in the reactor 70.

In a further embodiment, the EHC reactor 70 may comprise, for example, holding cells in which the material (or slurry) to be treated is pumped at regular time intervals; each cell can be connected to a spark production unit. The volume and number of cells (number of EHC modules) can be defined in such a way as to synchronize the timing of the hydrocarbonization, calibration, mixing, and EHC steps, so as to guarantee a flow of material in the various steps without interruption.

In one or more embodiments, the electric pulse generator for generating the EHC effect can be an electrical circuit as, for example, illustrated schematically in Figure 2, which uses resistors 100, a power supply-transformer 200 with rectifier 300, electrodes 600, energy-capacitor accumulators 400, and a spark gap 500.

The charging voltage (produced by the transformer 200, rectified) is accumulated in the capacitors 400, to then generate the high voltage pulse, regulated by the illustrated systems of the circuit, in particular by the spark gap 500. Preferably, an electrical circuit that can be used to generate the EHC effect also comprises current limiters (for example, at least one of the following: resistance, capacitor, inductance or combinations thereof).

When a spark is generated in an incompressible liquid, such as water, the high-voltage electric pulse generates high hydraulic pressures, which create shock waves with acoustic speeds that cover large volumes of liquid.

The phenomena that occur in the EHC 70 reactor are the following: i) the coal particles and the long molecular hydrocarbon chains break and dissociate; ii) the water molecules break down, producing hydrogen; iii) the coal hydrogenation reaction takes place; iv) the hydrogen molecules combine with the carbon- hydrogen molecules producing synthetic oil molecules.

In one or more embodiments, it is preferable to supply the pulse generator, for example, by means of a three-phase network since it is more economical and because the recharge times of the capacitive memory are reduced. The generated pulse is generally short and steep; the shape, the slope, the amplitude and the duration of the pulse are the determining factors of the EHC effect and essentially depend on the parameters of the circuit and also on the spark gap which, in particular, allows regulation of the discharge and the shape of the spark.

In one or more embodiments, Electro-Pulse Hydrogenated Cracking (EHC) can be carried out, for example, using the following regimes: a) Strong: with voltage higher than 50 kV and Capacity (capacitors) lower than 0.1 r|F, b) Medium: with voltage from 20 kV to 50 kV and Capacity between O.lpF and lpF and c) Soft: with voltage lower than 20 kV and Capacity greater than lpF.

In one or more embodiments, the pulses have a repetition frequency greater than 0.1 Hz, preferably between 0.1 and 1000 Hz, more preferably between 10 and 80 Hz. The choice of the circuit diagram and the specific devices can vary, and is determined based on the purposes of the process.

In one or more embodiments, the electric pulses generated in the Electro- Pulse Hydrogenated Cracking step are generated by an electric circuit with a voltage greater than 1 kV, preferably between 1 and 500 kV, more preferably between 5 and 80 kV.

In one or more embodiments, the electric pulses generated in the reactor for Electro-Pulse Hydrogenated Cracking last between 10 ns and 400 ps, preferably between 10 ns and 20 ps. In one or more embodiments, the rise time of the potential is, by way of example, between 0.5 and 3 kV/ns. In one or more embodiments, operating conditions that can be used in Electro-Pulse Hydrogenated Cracking include low voltage and long discharge times (soft regime), for example, 1-8 kV and times of 0.5-20 ps, or high voltage and short discharge times (medium/strong regime), still by way of example, 20-50 kV and times from tens of ns to 0.5 ps The soft regime produces greater quantities of synthetic oil, but the plant required is larger.

The energy consumption of the Electro-Pulse Hydrogenated Cracking (EHC) can be 15-150 Wh per kg of treated material. For example, to treat a material (or slurry) of 500 kg/hour, composed of coal (50%), water (25%) and oil (25%), with a“soft” configuration with continuous operation, consumption of electricity is around 25 kWh, equal to 50 Wh per kg.

In one or more embodiments, the material leaving the EHC reactor 70 can be collected in a collection tank 71 before being conveyed to the reactor 80 for the subsequent step.

In one or more embodiments, the mixture comprising coal obtained in the carbonization step ii), preferably by hydrocarbonization, and possibly supplemented with water and/or at least one oil and/or at least one liquid hydrocarbon can be directly subjected to plasma treatment.

In one or more embodiments, the plasma treatment is non-Local Thermodynamic Equilibrium (nLTE) conducted in at least one reactor comprising at least one plasma generator.

In one or more embodiments, the nLTE plasma generator is configured to generate plasma by means of, for example, an electric pulse generator. In one or more embodiments, the plasma can also be generated, for example, by induction or by microwaves.

In one or more embodiments, the nLTE plasma generator is configured to generate plasma by means of an electric pulse generator comprising at least one pair of electrodes.

In various embodiments, the electric pulses for generating the nLTE plasma are generated by an electric circuit by means of a voltage greater than 1 kV, preferably between 1 and 150 kV, more preferably between 1 and 10 kV.

In one or more embodiments, the electric pulses are generated with a frequency greater than 1 KHz, preferably between 5 and 100 KHz, more preferably between 5 and 20 KHz.

In one or more embodiments, the electric pulses last between 5 ns and 300 ps, preferably between 20 ns and 10 ps.

In one or more embodiments, the plasma generator is configured to generate plasma on the surface of a liquid, preferably a continuous flow of liquid to form a stable film having a thickness of between 0.5 mm and 1-3 mm.

In one or more embodiments, the mixture comprising coal obtained in step ii) of carbonization, preferably of hydrocarbonization, optionally supplemented with water and/or at least one oil and/or at least one liquid hydrocarbon or the mixture comprising synthetic fuel generated by Electro-Pulse Hydrogenated Cracking flows into the nLTE plasma reactor in the form of a continuous flow to form a stable film with a thickness of between 0.5 mm and 1-3 mm.

The plasma is generated in the gas between the electrodes and the continuous flow of the mixture, in the form of a liquid film following the generated electric field. In other words, the gas is brought to the plasma state, that is, electrons are formed, accelerated by the electric field, and ions.

The plasma is defined as cold or nLTE (non-Local Thermodynamic

Equilibrium), and the energy is generated by means of electric pulse generators.

In one or more embodiments, the method may comprise both Electro-Pulse Hydrogenated Cracking and non-Local Thermodynamic Equilibrium (nLTE) plasma treatment. In particular, in one or more embodiments, step iii) comprises:

- subjecting the mixture comprising coal to Electro-Pulse Hydrogenated

Cracking carried out in at least one reactor comprising at least one electric pulse generator, obtaining a mixture comprising synthetic petroleum and

- subjecting said mixture comprising synthetic petroleum to non-Local Thermodynamic Equilibrium (nLTE) plasma treatment carried out in at least one reactor comprising at least one nLTE plasma generator.

Therefore, the method may comprise a step in which the mixture comprising synthetic petroleum, water and any carbon residues obtained by Electro-Pulse Hydrogenated Cracking can also be subjected to nLTE plasma treatment.

In one or more embodiments, when the plasma treatment step follows the

Electro-Pulse Hydrogenated Cracking step, the mixture comprising synthetic fuel (synthetic petroleum), water and any carbon residues is conveyed into the plasma reactor 80 for the nLTE plasma treatment step.

The advantages of the plasma treatment step include, for example, the possibility of improving the quality of the synthetic petroleum obtained from the Electro-Pulse Hydrogenated Cracking (EHC) step. For example, plasma treatment of the synthetic petroleum makes it possible to improve the product if there is a) excessive presence of coal residues and b) excessive refining of heavy oil.

In one or more embodiments of the present description, the nLTE plasma treatment step is used both to increase the yield in terms of synthetic fuel production and to favor the formation of light synthetic oil compounds such as, for example, diesel fuel and gasoline.

In one or more embodiments, the nLTE plasma treatment step can be carried out by at least the activity of a pulse generator, for example, pulsed bipolar generator (which may have advantages over a continuous supply), at least one pair of electrodes, a system capable of generating a film of stable and continuous flowing material to be treated, on which the plasma acts. The configuration of the chamber can, therefore, vary to adapt to the needs of the material.

Applying an electric field with a determined potential (voltage>breakdown voltage) generates the state of plasma in the gas with the formation of ions and electrons, the latter with negligible mass, which are accelerated by the electric field. The electrons release energy favoring ionization processes, and the ions heat up to the temperature of thermal equilibrium (hot plasma). To ensure that the ions do not increase the temperature, the energy is generated in pulses, and consequently the thermal equilibrium (nLTE plasma) is not reached. Furthermore, it is preferable to use impulse voltages to avoid forming sparks, in order to improve the efficiency of the treatments.

In one or more embodiments, the plasma can be generated in the reactor 80 by means of a“crown” configuration in which the plasma is formed between two electrodes which can take various forms, for example, flat-tip, wire-cylinder, wire-plate, etc.

In one or more embodiments, the mixture composed of water, residual coal and synthetic petroleum leaving the Electro-Pulse Hydrogenated Cracking reactor 70 can be collected in a collection tank 71 and then conveyed to the reactor 80 for the subsequent step of nLTE plasma treatment, for example, by pumping.

In one or more embodiments, the plasma can be generated in a reactor 80 by means of, for example, a“crown” configuration, which can be made in a “wire-cylinder”, which represents a system that can be used industrially, even with multiple reactors in parallel for large flow rates.

As shown schematically in Figure 3A, in this embodiment, the reactor 80 comprises a metal receiving chamber 222, for example, a closed cylinder, in which the mixture comprising coal from the inlet 111, possibly with at least one oil and/or at least one liquid hydrocarbon (preferably obtained from the hydrocarbonization step), or the water- synthetic petroleum-coal residue mixture (obtained from Electro-Pulse Hydrogenated Cracking), is pushed tangentially in continuous supply, so as to assume a rotary motion on the inner walls of the chamber itself 222. The mixture flows into a cylinder with smaller diameter, plasma chamber 333, mounted coaxially on the bottom of the receiving chamber 222. The particles of the mixture move on the surfaces creating a spiral with the axis coinciding with the axis of the chambers 222 and 333.

The mixture in the form of a film flows on the walls of the chamber 333 in the area subjected to the plasma, and then leaves from the cylindrical duct from the lower base. The inner electrode 555 (made of titanium or similar material) is placed at the center of the plasma chamber 333 and the outer electrode 666 around the walls of the chamber 333.

The nLTE plasma is formed between the inner electrode 555 and the outer electrode 666, filling the space 444. It is also possible to introduce gas into the plasma area through a special inlet 777 in the area 444.

The mixture to be treated (slurry) that flows in the form of a film can have a thickness between 0.5 mm and 1-3 mm.

In one or more embodiments, the dimensions of the nLTE plasma reactor 80 are calculated based on the inlet diameter X mm of the plasma chamber 333, from which the 2X mm diameter of the receiving chamber 222, with a height of 0.8. X mm follows.

In one or more embodiments, the plasma can also be generated in a reactor

80 in a DBD configuration, or rather, in an environment confined by a dielectric barrier called DBD, dielectric barrier discharge (comprising, for example, quartz, glass, or ceramic). The advantage of this configuration is that spark formation is more easily avoided (although more complicated at the construction level).

An example of a reactor 80 comprising a plasma reactor in a DBD configuration is schematically illustrated in Figure 3B, where it can be seen that an electrode 191 is inserted inside a barrier container 999, for example, quartz, in which an electrolyte is fed through an inlet 112. Reference number 122 indicates an isolator and reference number 113 indicates the outlet of the electrolyte. This configuration can allow a longer life of the electrode itself. The most accepted explanation on the mechanism of cracking the molecules by means of nLTE plasma on liquid surfaces starts from the consideration that two neighboring carbon atoms, which are part of the heavy hydrocarbon molecule, have a stable connection, and in order to trigger a repulsive force between them (and to break the hydrocarbon molecule), it is necessary to induce a change in the rotation of an electron by means of, for example, high energies and magnetic fields. The effect of the nLTE plasma in contact with the material can generate replacement of a bound electron with a free electron of adequate energy and suitable direction of rotation, which causes repulsion and rupture of the molecule.

A gaseous medium is normally generated in the space between electrodes and the liquid film, at a temperature that remains much lower than the starting point of the raw material. Depending on the processes, gas can also be introduced, such as methane or the like.

In the case of using aqueous solutions, the action of the plasma leads to dissociation of the water molecules with the formation, among others, of free radicals, mainly (O) (H) and (OH). Chemical-molecular reactions are initiated in association with the breaking of bonds in the organic molecule, producing both liquefaction of the carbon and the production of light hydrocarbon molecules.

In one or more embodiments, the plasma treatment step can be carried out in the presence of catalysts, for example, solid or liquid microparticles of salts and metal oxides added to the gas and/or introduced into the reactor or, for example, if already used for the Electro-Pulse Hydrogenated Cracking (EHC) step. In one or more embodiments, oil and/or derivatives from refining methods including 140 and 161, and oils and/or liquid hydrocarbons 142, can be added to the reactor of the plasma treatment step, optionally pre-mixed with the slurry, optionally supplemented with catalysts 141, to further improve the performances.

An advantage brought about by both the nLTE plasma treatment step and by the Electro-Pulse Hydrogenated Cracking (EHC) step is the removal of any impurities in the synthetic fuels produced; for example, sulfur compounds are removed in the form of volatile or precipitated compounds.

The use of the nLTE plasma reactor in addition to the Electro-Pulse Hydrogenated Cracking reactor is justified from the point of view of energy consumption due to the increase in the production of synthetic oil, and due to the contribution to the cracking of the oil; by subjecting the material to this treatment, it is possible to enhance the conversion of coal into synthetic petroleum, and to favor the breaking of heavy molecules of synthetic petroleum. In this way, the production of diesel fuel and gasoline is increased and the quality is also improved.

The energy consumption parameterized on the mass of input material is, for example, 10-80 Wh per kg, generally 20 Wh per kg of mixture subjected to the nLTE plasma treatment.

In one or more embodiments, the method comprises a step of separating the mixture generated by the Electro-Pulse Hydrogenated Cracking (EHC) and/or by the nLTE plasma treatment step.

The separation step can be carried out in a separation system, for example, in a decanter 101 and in a three-phase disk centrifuge 102 in which the product is conveyed, for example, by pumping. Alternatively, self-cleaning filters or hydrocyclones, or similar functional systems, can be used for the first part of separating the solid.

In one or more embodiments, in order to improve the energy balance of the separation system, in particular for small capacity plants, a collection tank 90 can be inserted between the nLTE plasma treatment step reactor 80 and the separation system so as to make the system work cyclically in optimal conditions.

The separation system is connected to the tank to store the water 110, to be recirculated in the material preparation system 20 and/or to the mixing tank 60, and to the tank of the residual solid 103. Depending on the amount of carbon in the solid residues it is possible to recirculate the material in the holding tank 50 or in the mixing tank 60.

The yield in synthetic petroleum generated by the method subject of the present description is between 60 and 85% of the mass of coal supplied, on average about 75%. The percentage of the mass of the input material (waste and biomass) in anhydrous conditions is 40-65%.

The yield of synthetic petroleum production starting from biomass and waste is higher than the yield obtainable with known methods, such as, for example, the Fisher-Tropsch indirect liquefaction method, but also with respect to the direct conversion of carbon. For example, the Fisher-Tropsch indirect liquefaction method generally has a 20-25% yield on the anhydrous input material.

The energy efficiency of the process, which can be considered the ratio between the chemical energy of the products, minus the energy for its production, and that of the input material, is on average 70-85%, excluding energy recovery, while the comparison process (with waste and biomass supply) based on gasification and FT synthesis, considering the useful products (without deducting consumption) and the energy of the supplied material, has a yield of around 30%.

In one or more embodiments, the method comprises a step of refining the synthetic petroleum.

The synthetic petroleum generated by the aforesaid method consists of heavy hydrocarbon molecules from which lighter molecules with different boiling points and specific weights are formed, or rather, gasoline with a distillation temperature (at atmospheric pressure) of up to l75°C; kerosene with temperatures between l75°C and 250°C; diesel fuel with temperatures between 250°C and 380°C, and heavy oils at higher temperatures.

In one or more embodiments, producing light fractions is obtained by known state-of-the-art processes, regarding synthesis and, in general, with fractional distillation (separation of the fractions in relation to the boiling temperatures at atmospheric pressure); with vacuum distillation; with cracking, to modify the chemical structure (catalytic and hydrocracking); with reforming to modify the molecular structure (catalytic). A further refining process, known in the state-of-the-art, consists of cavitation followed by separation by selective membranes.

In one or more embodiments, in order to increase the transformation efficiency of the synthetic petroleum generated in light fractions, it is possible to use a cavitation system, placed downstream of the nLTE plasma reactor 80 or in place of this, if not provided.

Sonic or hydrodynamic or mechanical cavitation, or anything that induces the same effect, in addition to increasing the temperature, breaks the organic chains in order to obtain lighter petroleum products 120. The cavitation process induces, among others, the following effects: i) reducing any ash up to 1.5-2 times, ii) reducing any mechanical impurities up to 90%, iii) lowering (therefore improving) the freezing temperature ( cloud point ) and the CFPP ( Cold Filter Plugging Point), iv) increasing the cetane number, v) increasing the diesel fuel production.

In one or more embodiments, the step of refining and possibly upgrading the product can be carried out in a fractional distillation column. The synthetic petroleum deriving from the hydrogenated cracking step and/or from the nLTE plasma treatment 80, and possibly from the separation step 101 and 102 is fed, for example, with a pump for petroleum products, by means of a special tubular pipe, into a fractionation column 130. This column can be single or multiple, and also may envisage the reflux of products to improve efficiency and quality. In one or more embodiments of the described method, a single column at ambient pressure can be used.

In one or more embodiments, the refining and upgrading step comprises a step of heating the synthetic petroleum deriving from the Electro-Pulse Hydrogenated Cracking (EHC) and/or from the nLTE plasma reactor 80 and possibly from the separation step 101 and 102. The synthetic petroleum can be heated to a temperature ranging from 390 to 450°C, preferably 400°C in an evaporation area 131.

In one or more embodiments, the heat for this heating is provided by the fumes of the electrogenerator 170 (if applied to the process), possibly comprising an external fuel feeder 171, for example, by passing through the jacket of the pipes containing the synthetic oil, or in an evaporator that contains the pipes, and/or in integration with an HHO burner or with natural gas and/or with residual products from the refining and/or with electric plates.

In one or more embodiments, an acid reagent (in a quantity preferably between 0.1 and 0.8% of the synthetic petroleum mass) can be conveyed directly into the column 130, in order to remove any tar residues and/or unsaturated compounds. The acid reagent could also contribute to lowering the CFPP filtration temperature and the cloud point.

In one or more embodiments, the distillation column 130 is cooled, for example, by a water circuit 180 composed of free cooling modules with possible adiabatic closed-circuit sub-cooling 181.

In one or more embodiments, the products derived from the refining step (light products) are i) gasoline, extracted at a temperature of about l75°C and ii) kerosene extracted at a temperature of about 250°C. Medium products such as diesel fuel are extracted at temperatures between 250-380°C.

Gasoline, diesel fuel and kerosene are subsequently sent to special tanks, 160, 150, 161, while the heavy oils have a special tank 140.

Furthermore, any fractions of residual gas are sent, for example, to the electricity and heat generation system in an electro-generator or for thermal process uses.

The products obtained from the refining step are similar to those of fossil fuel petroleum, with a higher environmental quality, for example, due to the almost complete absence of sulfur and other pollutants typical of fossil products, as well as not generating the waste associated with extraction.

In one or more embodiments, the method comprises an upgrade step of the synthetic fuels produced.

In one or more embodiments, the upgrade step can be carried out by at least one of the following treatments: with unaltered zeolites, or doped with metal oxides, filtration, adsorption, cavitation, oxidation, stable mixing with water.

In one or more embodiments, the fuel produced can be supplemented with industrial additives, which are normally used in refineries. The diesel fuel fraction can be improved in quality, if necessary, for example, with additives such as a stabilizer additive 151 and a depressant additive 152, both commercially available. The use of these additives leads to extension of the preservation of the stored product, and an improvement in its cold properties. Furthermore, commercial additives can be used that improve the lubrication characteristics, the cetane number and other parameters in the tank 151 or 152. In one or more embodiments, the total percentage of additives can be, for example, from 0.5% to 5% of the treated synthetic fuel and, in any case, up to the achievement of target standards. Mixing with additives can be carried out, if necessary, with a mechanical cavitator, for example, to guarantee better stability of the product and reduce the consumption of additives.

The final product, such as diesel fuel, for example, is stored in a finished product tank 153, if necessary, depending on the application of the product, after appropriate filtration.

Gasoline obtained from the method described here can be supplemented with additives (commercially available and stored in a special tank 162), for example, to improve the anti -knocking properties (octane number). Additives can be added in a percentage, for example, between 0.5% and 5% of the treated product and, in any case, up to the achievement of target standards. The product is then stored in the appropriate finished product tank 163, if necessary, depending on the application of the product, after appropriate filtration.

Some results of the yield of products obtained with the described methods are reported below as a non-limiting example. Synthetic petroleum production can range from 60% to 85% of the coal fraction. The percentage referred to the mass of the input material (waste and biomass) in anhydrous conditions is 40-65%.

The method makes it possible to obtain, from the generated synthetic petroleum mass, 30-80% of diesel fuel; 20-50% of gasoline and kerosene, and 5- 30% of heavy oil. The described method can also allow production of electrical and thermal energy. For this purpose, it is preferable to install a cogeneration unit with an eight-cycle or diesel engine 170. If the objective is, for example, to produce diesel fuel, at least part of the gasoline produced can be used for the production of (for example) electricity; on the contrary, it is possible to use diesel fuel if the objective is gasoline production. Any residual gas from the refining column can be fed into the cogeneration unit. As an alternative to the electric generator, it is possible to generate steam from cooling of the hydrocarbonization reactor, and produce energy with known state-of-the-art methods such as, for example, using a steam engine. The hot fumes leaving the electrogenerator can be sent to the evaporator of the distillation column 131, to the hydrocarbonization reactor 40 and to the pre-carbonization tank 30 and to the emission point in the atmosphere 190. Each path can be isolated, so as to feed one or more target devices according to the needs of the process or directly to the emission point.

EXAMPLES

Below are non-limiting examples of the method for producing synthetic fuels from carbon-containing material, such as waste and biomass.

The carbon-containing material used as the starting material of the method described is as follows:

i) vegetable waste such as from pruning and public greenery with fragments of a maximum size of 200-250 mm;

ii) organic material from urban waste derived from recycling collection; iii) digestate derived from biogas production with a solid component of

25%.

The aforesaid material was subjected to the method described below, repeated three times. An analytical characterization of the material is shown in Table 1.

Table 1

ds = dry substance lev = lower calorific value

The material was manually loaded into an inlet hopper. Water (well water) was added to the hopper of the system for preparing materials 20 - in the case of pruning and organic urban waste - to obtain a material comprising an aqueous component of 75% and a solid component equal to about 25%.

The digestate derived from biogas used in the described method comprises a sufficient quantity of water (75%) and, therefore, water is not added to the hopper containing this material.

The material is loaded into the hopper of the system 20 and subsequently moved by a single-screw pump from 300 l/hour up to 2,000 l/hour.

The material is circulated twice between the hopper of the system 20 and a pre-carbonization tank 30 (to improve homogenization of the material) for a total of about 2.5 minutes in batch cycles, in addition to the manual handling times. The pre-carbonization tank 30 of 60 liters is made of stainless steel.

During circulation between the tank 30 and the system 20, an acetic acid catalyst is added so as to adjust the carbon-containing material to pH 6. Checking the pH is carried out in the tank with a portable pH-meter.

Table 2 indicates the quantity of material used for the described method.

Table 2

The material was manually loaded into a 50 liter reactor (a suitably adapted autoclave) for the carbonization step carried out by hydrocarbonization.

The reactor is made of stainless steel and can tolerate internal pressure values of up to 4 MPa (double the working pressures). The reactor also includes a control valve to avoid overpressure, and a 3 MPa emergency valve, with a pressure switch and thermostat to check the status of the process.

To obtain heating of the material in the reactor, an HHO production system was installed with burner and grate in tungsten and palladium (able to tolerate high temperatures). The flame has a temperature of around l,800°C. The system envisages the provision of an additional grate separated from the previous one by an air gap. The reactor is positioned on the second grate. The system does not emit fumes or harmful compounds.

The material, in a quantity of about 42 liters, is heated to a temperature of 2lO°C, in about 8-10 minutes, with an electrical consumption for the HHO generation system of 800 Wh.

Once the hydrocarbonization reactor 40 is loaded with the material, the air is excluded. The operating conditions for the hydrocarbonization step are the following: temperature of 210 °C, pressure 2 MPa, duration 1.5 hours. The temperature was reached in about 10 minutes.

During the process, the temperature was controlled with the alternating steps of ignition and switching off of the burner to avoid reaching a temperature above 2lO°C (the process is in fact exothermic).

At the end of the heating period, a cooling step was carried out at a temperature between 25 and 30°C.

After the hydrocarbonization step, the carbon component of the obtained mixture was separated from the water component by means of a small filterpress with an operating pressure of 7 bar (by a single-screw loading pump of 300 - 2,000 l/hour) and 50 pm polypropylene filter cloth with a 0.85 m surface area. The working capacity was 600 l/hour.

The water was collected for the subsequent steps and the moisture of the solid component of the material was measured with a hygrometer.

Below, in Table 3, the yield of petroleum produced by hydrocarbonization according to the starting material is indicated.

Table 3

The coal-containing material was loaded into a mixing tank, or rather, a 50 liter graduated transparent tank (in Plexiglas) with a special tap on the bottom, mounted on a metal stand.

In this tank, a mixture was prepared comprising coal (40% of the total mass of the mixture), water (54-55% of the mixture) and oil, with the kerosene from recirculation of the distillation step of the synthetic petroleum (4.8 - 5.8% of the mixture); components were mixed with a manual mixer. For the first tests, used motor oil was utilized, then in the final tests, the oil produced and set aside from each test was used, confirming that the process is indifferent to the type of oils/hydrocarbons used. A greater quantity of oils/hydrocarbons would have improved the performances, but the purpose was to establish minimum parameters.

The composition of the water-coal-oil mixture is shown in Table 4.

In order to proceed with the Electro-Pulse Hydrogenated Cracking (EHC) step, a tubular reactor (L=l500 mm and 3” diameter) was used in which two pairs of electrodes were inserted at a symmetrical distance.

Each pair of electrodes was powered by a high voltage electric pulse generator.

The reactor was placed on a slight slope and connected to the bottom of the

Plexiglas mixing tank, which was raised with respect to the axis of the reactor, and to the return pump.

The mixture comprising coal deriving from the mixing tank flows into the EHC reactor and after this step it is conveyed back into the initial mixing tank by means of a single- screw pump.

The water-coal-oil mixture is subjected to the EHC step twice each time. The circulation is repeated 7 times, simulating a reactor with 14 pairs of electrodes.

A three-phase network power supply was used, with a pulse voltage 8 kV, pulse 0.5 ps, frequency 10 Hz (soft configuration).

At the end of the Electro-Pulse Hydrogenated Cracking EHC step, the product obtained was a mixture comprising synthetic petroleum, water and solid residues (including coal parts) and was collected in the graduated mixing tank of 50 1.

From the mixing tank, the mixture was subjected to the plasma treatment step.

The mixture was pumped tangentially into an inlet chamber of an nLTE plasma reactor.

The reactor has a flow rate of 200 l/hour (3 l/min), and produces a liquid film with an average thickness of 0.5 - 0.7 mm.

The inlet chamber is a cylinder with a diameter of 50 mm and a height of 20 mm, and the plasma chamber has a diameter of 26 mm.

The pulse generator used as a plasma source generates pulses with a 10 KHz frequency, 5 kV voltage and 10 ps pulse duration.

The mixture was treated for 5 minutes. Subsequently the product derived from the plasma treatment - comprising synthetic petroleum, water and solid residues (normally residual ash from the source material) - was conveyed in centrifugal discs with a flow rate of 200 l/hour.

The calorific value of the synthetic oil obtained was assessed by“Mahler's bomb”.

Table 5 shows the results relating to the production of synthetic petroleum after the mixture was subjected to the EHC step and to the nLTE plasma treatment step.

Table 5

In summary, the synthetic petroleum production yield obtained with the described method is between 38% and 49% with respect to the dry starting material and is between 61% and 72% with respect to the coal obtained after the hydrocarbonization step.

The yield of synthetic petroleum obtained with the described method is higher than the yield obtainable with known technologies, or rather, compared to gasification and FT synthesis methods which, on average, have a yield of 20-25% compared to the input material, but also compared to direct liquefaction methods of the coal. Furthermore, direct liquefaction methods have the disadvantage of requiring critical operating conditions (pressures of up to 300 atm) and expensive installations (such as, for example, hydrogenation systems).

The method subject of the present description is simple and easily controllable.

The energy consumption for producing synthetic petroleum for the treated masses is, on average, 3,510 Wh (average value obtained by adding the consumption for the different steps of the method).

To have a result comparable with the chemical energy of the products and of the inlet material, the electric -thermal conversion is carried out with a 25% conversion factor (by analogy with the conversion value in tons of oil equivalent (toe) from electricity). Therefore, the chemical energy needed to produce synthetic petroleum is on average 12,000 kcal for the tests, with a +/- 10% difference between the various tests.

Furthermore, the energy efficiency of the synthetic oil production method was calculated (with an average calorific value of 8500 kcal/kg), i.e. the ratio between net energy produced (energy content of synthetic oil - energy consumption for its production) and energy content of the input material (anhydrous).

The results obtained indicate average energy efficiency values of 72% for public greenery-pruning, 71% for urban waste, and 72% for digestate. Only in terms of comparison, the energy efficiency of gasification and FT synthesis methods for the same starting materials is on average 30% (considering only the relationship between the energy of the materials produced and of the input materials, without considering the consumption).

The synthetic oil obtained was subjected to the distillation step, and the various fractions were weighed. The results obtained are indicated in Table 6.

Table 6

In summary, with reference to gasoline and kerosene, the yield is 19%- 32% with respect to synthetic oil; 14%- 19% with respect to coal and 9%-l2% compared to the dry mass input.

With reference to diesel fuel, the yield is 52-64% of the mass of synthetic petroleum, equal to 32%-46% of the mass of coal and 20%-3l% of the dry mass input.

With regard to obtaining heavy oil, the yield is 16%-17% of the mass of synthetic petroleum, equal to 10%- 12% of the mass of coal and 6%-8% of the dry mass input.

The results obtained therefore show that the described method is particularly efficient in the production of synthetic fuels.

Diesel fuel and gasoline produced by urban waste were also analyzed for an assessment of the quality of the final product. Products derived from three repetitions of the described method were mixed in order to obtain an average evaluation.

For producing diesel fuel and gasoline, no acid additives were added before distillation, confirming that the nLTE plasma material treatment step optimizes the quality of the products. Specific commercial multifunctional additives only were added to the diesel fuel and gasoline, in quantities of 1% by weight for diesel fuel and 2.5% by weight for gasoline.

Table 7 indicates the characteristics of the diesel fuel obtained with the method described starting from organic urban waste.

Table 7

NR not recordable

Table 8 indicates the characteristics of the gasoline obtained with the method described starting from the organic urban waste.

Table 8

NR not recordable

The indicated results demonstrate - for the described method - a higher efficacy in the production of synthetic fuels starting from biomass and waste with respect to known methods that are currently available.

The method subject of the present description also has the advantage of being equipped with high energy efficiency, of requiring very simple instruments and installations with consequent limitation of production costs.

The method is also extremely advantageous from the environmental impact point of view as it helps to reduce climate -changing emissions and solve the problem of waste and residual biomass that very often represent critical issues for their disposal.